title: Nb2O5·nH2O as a heterogeneous catalyst with water-tolerant Lewis acid sites.
abstract: Niobic acid, Nb(2)O(5)·nH(2)O, has been studied as a heterogeneous Lewis acid catalyst. NbO(4) tetrahedra, Lewis acid sites, on Nb(2)O(5)·nH(2)O surface immediately form NbO(4)-H(2)O adducts in the presence of water. However, a part of the adducts can still function as effective Lewis acid sites, catalyzing the allylation of benzaldehyde with tetraallyl tin and the conversion of glucose into 5-(hydroxymethyl)furfural in water.
authors.affiliation: Materials and Structures Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan.
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Nakajima
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Baba
authors.forename: Ryouhei
authors.initials: R
authors.lastname: Noma
authors.forename: Masaaki
authors.initials: M
authors.lastname: Kitano
authors.forename: Junko N
authors.initials: JN
authors.lastname: Kondo
authors.forename: Shigenobu
authors.initials: S
authors.lastname: Hayashi
authors.forename: Michikazu
authors.initials: M
authors.lastname: Hara